Canada - Memorial University of Newfoundland

Table 4.2 Standard state properties ofthe first and second ionizations of phosphoric
acid
H 3P04(aq) + OI1(aq) ... H1P04'(aq) +H20(1)
H 2POdaq) + OH"(aq) .. HPOi"(aq) +H2O(I)
t P d H20 togK .6.,06 I'..rHQ !'J.,s6 Q
"yo !:J.,Cp
"C b"" g·cm') cal-morl cal-morl cal·mor1·K1 cmJ·mOr1 ca[·mor1 .K'l
1"1 ionization
25.00 1.000 0.997 11.825 -16133 -15240 2.9 5.5 20.2
50.00 1.000 0.988 10.972 -16224 -14789 4.3 4.0 16.5
75.00 1.000 0.975 10.261 -16347 -14395 5.5 3.3 15.2
100.00 1.013 0.958 9.662 -16498 -14019 6.5 3.2 14.9
125.00 2.320 0.939 9.152 -16673 -13645 7.5 J.3 15.1
150.00 4.757 0.917 8.714 -16873 -13265 8.4 J.8 15.3
175.00 8.918 0.892 8.336 ·17094 -12882 9.3 4.5 15.3
200.00 15.536 0.865 8.008 -17337 -12499 10.1 5.3 15.5
225.00 25.479 0.834 7.721 -17599 -12108 10.9 6.2 15.9
250.00 39.736 0.799 7.469 -17880 -11726 11.7 7.2 14.2
275.00 59.431 0.759 7.247 -18176 -11484 12.1 7.5 1.6
300.00 85.838 0.712 7.043 -18471 -11870 11.5 2.6 -52.6
2""ionization
25.00 1.000 0.997 6.790 -9263 -12335 -10.3 -3.7 -0.5
50.00 1.000 0.988 6.089 -9004 -12349 -10.4 -5.7 -0.7
75.00 1.000 0.975 5.489 -8744 -12372 -lOA -6.8 -1.2
100.00 L013 0.958 4.967 -8482 -12408 -10.5 -7.5 -1.8
125.00 2.320 0.939 4.510 -8217 -12461 -10.7 -8.1 -2.5
150.00 4.757 0.917 4.105 -7948 -12534 ·10.9 -8.6 -3.3
175.00 8.918 0.892 3.743 -7675 -12627 -11.1 -9.1 -4.2
200.00 15.536 0.865 3.417 -7397 -12747 -11.3 -9.6 -5.6
225.00 25.479 0.834 3.120 -7112 -12915 -11.7 -10.4 -8.2
250.00 39.736 0.799 2.849 -6819 -13154 -12.1 -11.6 -ll.5
275.00 59.431 0.759 2.597 -6515 -13456 -12.7 -13.5 ·13.0
300.00 85.838 0.712 2.365 -6201 -13695 -13.1 -15.1 -3.9
99